WASHINGTON — Former Energy Secretary Steven Chu is joining the board of directors of a Canadian company that says it has a cost-effective way to capture and reuse carbon dioxide from power plants fired by coal and natural gas.

Vancouver-based Inventys Thermal Technologies says it has developed a process that it says uses less energy than conventional carbon capture techniques and is less expensive.

A Nobel Prize-winning physicist, Chu served as energy secretary in President Barack Obama’s first term and now teaches physics at Stanford University.

“It’s a cause I believe in, and it is also something that has a shot at working,” Chu said in an interview Tuesday. He was referring to so-called carbon-capture technologies, which are intended to limit pollution blamed for global warming.

The process removes or captures heat-trapping carbon dioxide produced by power plants and other sources, preventing it from being released into the atmosphere. The captured carbon can be stored underground or used to stimulate recovery of leftover oil from old oil fields.

The technique used by Inventys “is a new approach,” Chu said, and “like any start-up company there’s a high-risk about it.”

Chu, who left office in April, said Inventys recruited him not just for his political contacts, but also for his technical knowledge. “I don’t want to be part of the ex-Washington scene of people trying to cash in because they know people or can open doors,” he said.

Chu’s move comes as the Obama administration announced plans to offer up to $8 billion in loan guarantees for carbon-capture technologies that can be applied to a range of pollution sources. Several demonstration projects are now underway, including a large plant in Port Arthur, Texas, that began operations last year.

Chu declined to identify a second company where he also serves on the board of directors, saying only that it is U.S.-based and “has a very different approach to hydrocarbon fuels.”

As energy secretary, Chu was credited with boosting renewable energy such as wind and solar power, but he was criticized for his handling of a $500 million federal loan to solar panel maker Solyndra, which later went bankrupt, laying off 1,100 workers.